Oral rehydration solutions assist in rehydrating an individual after there has been a substantial loss of fluid, resulting in the individual experiencing dehydration. In both developing and developed countries, this dehydration is sometimes associated with benign activities such as sport. However oral rehydration solutions can also have a lifesaving role, where the cause of dehydration is not only through physical exertion or activity, but a consequence of a disease, such as excessive diarrhoea caused by, for example, rotavirus.
“Dehydration” as used herein, means a condition resulting from excessive loss of body fluid that occurs when an output of fluid exceeds a fluid intake.
Dehydration can be a significant problem. A 2% loss of body weight in fluids can diminish human performance in a number of areas (S. I. Barr, “Effects of dehydration on exercise performance”, Can. J. Appl. Physiol., 24, 164-172, 1999). Dehydration can occur, for example, in situations where an individual excessively sweats due to participation in a sport, or through medical conditions such as diarrhoea.
Dehydration Caused by Physical Activity
An individual taking part in intense exercise can lose approximately 1 to 3 litres of fluid in an hour (N. J. Rehrer, “Fluid and electrolyte balance in ultra-endurance sport”, Sports Med., 31, 701-715, 2001). This loss of fluid may be increased by exercising in a hot environment.
With regards to sports, during a football game or intensive training session Australian football league (AFL) players can lose between 1.15-3.45% of their body weight (Adelaide Football Club internal studies), due to fluid loss. This degree of fluid loss will result in a diversion of blood volume to kidneys and other vital organs with a reduced flow of fluids to muscles. An unfortunate consequence of this fluid diversion is a delay in muscle recovery for a player. Current sports drinks consumed by players during and after a game have a high glucose content, much higher than in proven rehydration solutions. Because the glucose content is high (hyperosmolar to body fluids), the sports drinks are inefficient for hydration, leading to a slower than achievable water absorption and only utilising the absorptive capacity of the small intestine and not the large intestine.
Water and salt absorption through the large intestine requires the presence of short chain fatty acids (SCFAs) which are fermented by colonic bacteria from carbohydrates. Direct ingestion of SCFAs is not an option as the SCFAs are absorbed by the small intestine before reaching the large intestine. Instead, an individual can ingest resistant starch (RS) (starches resistant to digestion), such as high amylose maize starch. These resistant starches can be found in baked foods and increase the absorption of water and salts in the large intestine in order to facilitate and enhance hydration in an individual.
Herein, beverages comprising a resistant starch, and oral rehydration compositions and solutions comprising a resistant starch are disclosed. Ingestion of these beverages, oral rehydration compositions or solutions, can enable an individual participating in a physical activity, for example a sport, to ensure they are sufficiently hydrated in order to: effectively prepare for participation in the physical activity; maintain their level of performance during the physical activity; and efficiently recover from said physical activity.
It is an aim of the present invention to provide oral rehydration compositions and solutions which show efficacy in the treatment of dehydration in individuals due to physical activity, including a sport, by formulating oral rehydration compositions which comprise starches that comprise resistant starch. These oral rehydration compositions and solutions can be consumed prior to the physical activity to ensure adequate hydration to enable an individual to participate in a physical activity, such as a sport. Alternatively, or additionally, these oral rehydration solutions can be consumed following a physical activity, such as a sport, in order to rehydrate an individual. In addition, the oral rehydration solutions can be consumed during a physical activity to ensure that an individual maintains adequate hydration for continued participation in the physical activity. These oral rehydration solutions can be consumed in combination with a food item that comprises a starch comprising a resistant starch, or an additional drink that comprises a starch comprising a resistant starch.
It is also an aim of the present invention to provide beverages that comprise a resistant starch, said beverages can be consumed be an individual before, during or after the individual undertakes a physical activity (for example a sport). The beverages can be consumed prior to the physical activity to ensure adequate hydration to enable an individual to participate in a physical activity, such as a sport. Alternatively, or additionally, the beverages can be consumed following a physical activity, such as a sport, in order to rehydrate an individual. In addition, the beverages can be consumed during a physical activity to ensure that an individual maintains adequate hydration for continued participation in the physical activity. The beverages can be consumed in combination with a food item that comprises a starch comprising a resistant starch, or an additional drink that may comprise a resistant starch.
Dehydration Caused by Diarrhoea
The World Health Organisation (WHO) states that diarrhoea is the second leading cause of death among children under five globally (The United Nations Children's Fund (UNICEF)/World Health Organization (WHO), Diarrhoea: Why children are still dying and what can be done). The diarrhoea can be caused by a number of conditions, including diseases such as cholera. According to WHO statistics only 39 percent of children suffering with diarrhoea receive the recommended treatment, which is oral rehydration therapy with continued feeding (from 2004 to present).
Currently, oral rehydration therapy consists of the delivery of a formulation that typically includes water and oral rehydration salts, the rehydration salts being a combination of sodium chloride, glucose (anhydrous), potassium chloride and trisodium citrate (dihydrate). Some rice-based oral rehydration therapies are also available.
The WHO has produced a reduced osmolarity oral rehydration solution to replace its previous standard oral rehydration solution (ORS). The recommended formulation for the reduced osmolarity oral rehydration solution is shown in Table 1. The WHO recommends a 10% tolerance with the recited values of the components recited in Table 1.
TABLE 1WHO/UNICEF Recommendations for concentrationsof components present in their reduced osmolarityoral rehydration solution.Recommended concentration inElement/currenta) WHO/UNICEF ReducedCompoundOsmolarity ORS/mmol/L.Sodium75Chloride65Potassium20Citrate10Glucose75Total osmolarity of 245 mOsmol/La)recommended values at 4 Sep. 2012.
Despite the WHO promoting oral rehydration solutions, these solutions have not achieved the wide-spread use that was initially expected. Although this may be due in considerable part to a lack of knowledge or appreciation of the effects of oral rehydration solutions, those in the developing world have been reluctant to use them as there is not a palpable effect in reducing diarrhoea despite evidence that they do provide a benefit, to a limited degree, in reducing the risk of dehydration and, in some cases, reducing the risk of death due to dehydration. Therefore, improved formulations need to be devised in order for the communities who need them to take them seriously and utilise them in the treatment of dehydration.
It is an aim of the present invention to provide oral rehydration compositions which show efficacy in the treatment of dehydration, including dehydration caused by diarrhoea, by formulating oral rehydration compositions which comprise a starch that comprises a resistant starch.